The number of catastrophic wildfires in the U.S. has been
steadily rising. The nation has spent more than $1 billion annually
to suppress such fires in eight of the past 10 years. In 2005
a record 8.7 million acres burned, only to be succeeded by 9.9
million acres in 2006. And this year is off to a furious start.
To a great extent, the increase in fires stems from a buildup
of excess fuel, particularly deadwood and underbrush. Forests
harbor more fuel than ever in large part because for decades,
land management agencies, including the U.S. Forest Service,
have followed a policy of trying to quickly put out every fire
that starts. Fires, however, can clear out debris, preventing
material from accumulating across wide areas and feeding extremely
large, intense fires that become impossible to fight. Even in
the absence of such a policy, firefighters find themselves compelled
to combat many blazes because people continue to build homes
further into wildlands, and those structures require protection.
Exacerbating the problem, spring snowmelts have been occurring
earlier, extending the number of weeks every year when forests
are exposed and dangerously dry.